Quantum dot modulation for displays

ABSTRACT

Modulated light sources are described. A modulated light source may have first light sources that are configured to emit first light, which has first color components that occupy a range that is beyond one or more prescribed ranges of light wavelengths. The modulated light source may also have a light converter that is configured to be illuminated by the first light. The light converter converts the first light into second light. The second light has one or more second color components that are within the one or more prescribed ranges of light wavelengths. Strengths of the one or more second color components in the second light are monitored and regulated to produce a particular point within a specific color gamut.

CROSS-REFERENCE TO RELATED APPLICATIONS

This Application claims benefit of priority to related, co-pending U.S.Provisional Patent Application No. 61/424,199 filed on Dec. 17, 2010;U.S. Provisional Patent Application No. 61/448,599 filed on Mar. 2,2011; U.S. Provisional Patent Application No. 61/486,160 filed on May13, 2011; U.S. Provisional Patent Application No. 61/486,166 filed onMay 13, 2011; and U.S. Provisional Patent Application No. 61/486,171filed on May 13, 2011, which are hereby incorporated herein by referencefor all purposes as if fully set forth herein.

TECHNOLOGY

The present invention relates generally to light sources, and inparticular, to modulated light sources.

BACKGROUND

To display images, a display system may contain light valves and colorfilters that regulate brightness levels and color values of pixels asthe pixels are being illuminated by a light source, such as back lightunits (BLUs). Typically, light sources such as fluorescent lights orlight-emitting diodes illuminate pixels on display panels. The lightilluminating the pixels is attenuated by RGB color filters and liquidcrystal materials. As a result, brightness levels and color values maybe controlled on a pixel-by-pixel basis to express an image based onreceived image data. In most display systems, a light source illuminatespixels with white light comprising a broad spectrum of wavelengths. Asthe white light from the light source is color-filtered by color filtersand brightness-regulated by different states of a liquid crystalmaterial, a color gamut is formed by all possible color values of thepixels and may be used to support displaying color images.

Most optical configurations of display systems are optimized for one ormore intermediate points of a wavelength spectrum. Existing lightsources provide diffusive, wide ranges of wavelengths includingwavelengths for which the optical configurations are not optimized. Evenfor those single color light sources, the emitted light in the existinglight sources is still composed of wide ranges of wavelengths. As thesewide ranges of wavelengths include most wavelengths for which thedisplay systems are not optimized, image inversions, restrictive viewingangles and undesirable color representations and tinges may occur in thedisplay systems with existing light sources so that displayed imagessuffer from poor quality.

The approaches described in this section are approaches that could bepursued, but not necessarily approaches that have been previouslyconceived or pursued. Therefore, unless otherwise indicated, it shouldnot be assumed that any of the approaches described in this sectionqualify as prior art merely by virtue of their inclusion in thissection. Similarly, issues identified with respect to one or moreapproaches should not assume to have been recognized in any prior art onthe basis of this section, unless otherwise indicated.

BRIEF DESCRIPTION OF DRAWINGS

The present invention is illustrated by way of example, and not by wayof limitation, in the figures of the accompanying drawings and in whichlike reference numerals refer to similar elements and in which:

FIG. 1A, FIG. 1B, and FIG. 1C illustrate example modulated lightsources, according to possible embodiments of the present invention;

FIG. 2A and FIG. 2B illustrate example display systems that comprisemodulated light sources, according to possible embodiments of thepresent invention;

FIG. 3 illustrates an example light modulation tile array, according topossible embodiments of the present invention;

FIG. 4A, FIG. 4B, FIG. 4C, and FIG. 4D illustrate example lightmodulation tiles, according to possible embodiments of the presentinvention;

FIG. 5 illustrates a block diagram of an example modulated light source,according to possible embodiments of the present invention;

FIG. 6 illustrates an example process flow, according to a possibleembodiment of the present invention; and

FIG. 7 depicts an example color gamut, according to an embodiment of thepresent invention.

DESCRIPTION OF EXAMPLE POSSIBLE EMBODIMENTS

Example possible embodiments, which relate to modulated light sources,are described herein. In the following description, for the purposes ofexplanation, numerous particular details are set forth in order toprovide a thorough understanding of the present invention. It will beapparent, however, that the present invention may be practiced withoutthese particular details. In other instances, well-known structures anddevices are not described in exhaustive detail, in order to avoidunnecessarily including, obscuring, or obfuscating the presentinvention.

Example embodiments are described herein according to the followingoutline:

-   -   1. GENERAL OVERVIEW    -   2. MODULATED LIGHT SOURCES    -   3. LIGHT SENSORS AND REGULATORS    -   4. OPTICAL STACK    -   5. PATTERNED MODULATION    -   6. UNPATTERNED MODULATION    -   7. INTENSITY STATES    -   8. INTENSITY STATES    -   9. MODULATED LIGHT SOURCE CONTROLLER    -   10. EXAMPLE PROCESS FLOW    -   11. EQUIVALENTS, EXTENSIONS, ALTERNATIVES AND MISCELLANEOUS        1. General Overview

This overview presents a basic description of some aspects of a possibleembodiment of the present invention. It should be noted that thisoverview is not an extensive or exhaustive summary of aspects of thepossible embodiment. Moreover, it should be noted that this overview isnot intended to be understood as identifying any particularlysignificant aspects or elements of the possible embodiment, nor asdelineating any scope of the possible embodiment in particular, nor theinvention in general. This overview merely presents some concepts thatrelate to the example possible embodiment in a condensed and simplifiedformat, and should be understood as merely a conceptual prelude to amore detailed description of example possible embodiments that followsbelow.

Techniques for providing modulated light sources that emit light ofwavelengths within prescribed ranges of light wavelengths are described.In some possible embodiments, a modulated light source as describedherein comprises one or more (light) modulation layers that may bestimulated by incident broadband first light to regenerate second lightwithin prescribed ranges of light wavelengths. The regenerated secondlight may be used to illuminate image pixels in a display system.

In some possible embodiments, the modulation layers may comprise quantumdots selected based on their physical properties including a property ofemitting regenerated light with one or more (e.g., a set number of)color components. Each of the one or more color components isparticularly colored light within a prescribed range of (light)wavelengths for a particular color. In some possible embodiments,prescribed ranges of light wavelengths do not vary with operatingtemperatures of the modulated light source, thereby allowing an accuratecomposition of light wavelengths in regenerated light across a widerange of operating temperatures. Furthermore, (light) intensities ofcolor components in the regenerated light as described herein may bemonitored and regulated. As a result, the regenerated light possesses anaccurate profile of light wavelengths and intensities, even when lightmodulation materials age. A modulated light source as described hereinmay be used in a high-end display system as a part of an optical stack,which may additionally and/or optionally comprise other opticalcomponents such as color filters and/or color enhancer(s), to set pixelsat various color values and brightness levels. The accurate profile oflight wavelengths and intensities in the regenerated light may result inilluminating pixels in the display system with white light at aparticular white point (e.g., D65) in a color gamut supported by thedisplay system. Thus, images created by the display system may be highlyaccurate in terms of color values.

Under the light modulation techniques as described herein, the maximumnumber of groups of distinct quantum dots in modulation layers may beconfigurable as a set number, for example, one, two, three, four, five,six, or another positive integer. While three primary color componentsmay be sufficient in most display systems, modulated light sources asdescribed herein may, but are not limited to, provide more (or fewer)color components than three. In particular, under techniques asdescribed herein, a modulated light source comprising a sufficientnumber of color components may be used together with other opticalcomponents to support a wide color gamut (WCG) in a high quality displaysystem.

Modulation layers in modulated lights sources as described herein may bepatterned and/or unpatterned. A fully patterned modulation layer maycomprise an array of light conversion units each of which may comprisedistinct areas. Each of the distinct areas in a light conversion unitmay emit a part of a single color component in regenerated light. Afully unpatterned modulation layer may comprise an array of lightconversion units each of which may emit parts of all color components inregenerated light. A patterned modulation layer may also comprise anarray of light conversion units each of which may emit a part of somebut not all color components in the regenerated light. A mixed patternedmodulation layer may also be used and may comprise an array of a mixtureof single-color light conversion units, two-color light conversionunits, up to fully mixed all-color light conversion units. In somepossible embodiments, modulation layers may be disposed before or afterLCDs and color filters in optical stacks of display systems.

Through a patterned modulation layer as described herein, first lightfrom broadband light sources may be converted into regenerated secondlight with particular color components including light with brightened(e.g., highly saturated) color. Thus, a modulated light source asdescribed herein may be used to extend the color gamut of a high qualitydisplay system such as an HDR display.

Intensities of regenerated light from each area of a light modulationlayer as described herein may be measured and regulated. The absoluteintensity of a color component for anyone of the light conversion unitsin the modulation layer may be regulated. The relative intensity of acolor component for the light conversion unit may also be measured andregulated relative to one or more other color components for the lightconversion unit. In some possible embodiments, a light conversion unitis coupled to one or more pulse-width modulation (PWM) control signalssuch that the relative and/or absolute intensities of color componentsin a modulation layer or a light conversion unit therein may becontrolled between a minimum intensity and a maximum intensity. Thus, amodulated light source as described herein is configured to support notonly a wide color gamut but also a highly dynamic range of contrastlevels, helping a display system to produce highly accurate and detailedimages.

A modulated light source as described herein may operate in place of, oralternatively in addition to, other light sources (of a same ordifferent type) in a single system (e.g., a single display system). Forexample, a modulation layer in the modulated light source may enhancecolors and brightness levels for certain pixels based on local colorconcentrations or other chromatically related features of a givenspatial area based on image data, while the pixels may be illuminated byanother light source to express colors and brightness levels through,for example, LEDs and color filters. Thus, the display system'ssensitivity to the image data may be increased (e.g., made more narrow)by modulating activation of quantum dots in a given area of the display.The quantum dots may also be used to compensate for incorrectconcentrations of LEDs of particular emission color bands in a displaysystem. This can be used to produce a cost-effective lighting solutionthat corrects or compensates for color shifts in RGB LEDs that bythemselves may vary with temperature and driver electric current.

In some possible embodiments, mechanisms as described herein form a partof a display system, including but not limited to a handheld device,game machine, television, laptop computer, netbook computer, cellularradiotelephone, electronic book reader, point of sale terminal, desktopcomputer, computer workstation, computer kiosk, and various other kindsof terminals and display units.

Various modifications to the preferred embodiments and the genericprinciples and features described herein will be readily apparent tothose skilled in the art. Thus, the disclosure is not intended to belimited to the embodiments shown, but is to be accorded the widest scopeconsistent with the principles and features described herein.

2. Modulated Light Sources

FIG. 1A illustrates example modulation light source 100 in accordancewith some possible embodiments of the present invention. The modulationlight source 100 comprises a light converter 102 and one or more firstlight sources 104. As used herein, a light converter as described hereinmay be of any physical shape such as a shape with planar surfaces orcurved surface, a cubic shape, a cylindrical shape, a shape with regularor irregular contours, etc. For the purpose of illustration only, thelight converter 102 may be a (light) modulation layer and may have oneor more planar or curved surfaces through which regenerated light fromthe light converter 102 is to be projected out.

The one or more first light sources 104 may or may not be modulated, andmay emit first light 106, at least some of which has wavelengths no morethan one of one or more threshold wavelengths. The one or more thresholdwavelengths may be intrinsic properties of, and thus determined by,light conversion materials in the light converter 102. The lightconversion materials (e.g., quantum dots) in the light converter 102,when illuminated by the first light 106 with wavelengths no more thanone of the one or more threshold wavelengths, is configured toregenerate second light 108 with different wavelengths than thewavelengths of the incident first light. Like the threshold wavelengthsfor light regeneration, the wavelengths in the second light 108 may beintrinsic properties of, and thus determined by, physical attributes ofthe light conversion materials such as the quantum dots. In somepossible embodiments, the physical attributes, including types, sizes,shapes, etc., of the quantum dots may be particularly chosen such that,when illuminated by first light 106 from the first light sources 104,the light converter 102 regenerates the second light 108 compriseswavelengths within one or more prescribed ranges of wavelengths. In aparticular possible embodiments, the second light 108 comprises onlywavelengths within one or more prescribed ranges of wavelengths

In some possible embodiments, the first light 106 comprises colorcomponents, at least one of which possesses light wavelengths that aredistributed across a broad range of wavelengths. For example, the firstlight sources may comprise (broadband) light-emitting diodes (LEDs). TheLEDs may generate one or more color components (e.g., RGB). Each colorcomponent from the LEDs may possess light wavelengths distributed acrossa broad range of light wavelengths.

The second light 108, on the other hand, may comprise color componentswith wavelengths in their respective prescribed ranges of wavelengths.For example, each color component (e.g., red color component) in secondlight 108 may possess wavelengths within a corresponding one of theprescribed ranges of wavelengths. In a particular possible embodiment,each color component (e.g., red color component) in second light 108 maypossess only wavelengths within a corresponding one of the prescribedranges of wavelengths (e.g., a narrow range of red light wavelengths,among the prescribed ranges of wavelengths, to which the red colorcomponent corresponds). In some possible embodiments, the number ofcolor components in second light 108 may be preconfigured to a setnumber before the modulated light source 100 is used, for example, in adisplay system. The color components in second light 108 may form a setof primary colors that can be used to produce a particular white point(e.g., D65 as defined by the International Commission on Illumination(CIE)) in a color gamut supported by the display system.

As used herein, the term “a prescribed range of wavelengths” may referto a narrow, contiguous range of light wavelengths. In some possibleembodiments, a prescribed range of wavelengths may be a range with amaximum width of one (1) nanometer. In some possible embodiments, aprescribed range of wavelengths may be a range with a maximum width offive (5) nanometers. In some possible embodiments, a prescribed range ofwavelengths may be a range with a width that is smaller than one (1)nanometer. In some possible embodiments, a prescribed range ofwavelengths may be a range with a width that is smaller than five (5)nanometers. In some possible embodiments, a prescribed range ofwavelengths may be specified as ratios between a first width of a firstrange of wavelengths as produced by first light 106 and a second widthof a second range of wavelengths as produced by second light 108. Forexample, the first light source 104 may produce the first light 106 thathas a blue LED color component, across a first range of wavelengthshaving a first width of 20 nanometers. The light converter 102, on theother hand, may be configured to convert the first light 106 into thesecond light 108 such that a blue color component in the regeneratedsecond light 108 has a prescribed range of wavelengths with a secondwidth that is a percentile of the first width of the first range ofwavelengths. This percentile may be 2, 5, 10, 20, 50, or other smalleror larger percentile. Analogously, the same blue LED color component infirst light 106 may cause the light converter 102 to regenerate a redcolor component in the second light 108, the red color component havinga prescribed range of wavelengths with a width that is anotherpercentile of the first width of the first range of wavelengths. Thispercentile may be 2, 5, 10, 20, 50, or other smaller or largerpercentile.

3. Light Sensors and Regulators

FIG. 1B illustrates an alternative configuration of an example modulatedlight source 100 in accordance with some possible embodiments of thepresent invention. In some possible embodiments, the modulated lightsource 100 may additionally and/or optionally comprise one or more lightsensors 110. The light sensors 110 may be configured to takemeasurements of wavelengths and strengths of color components in firstlight 106 and/or second light 108. In some possible embodiments, thelight source 100 may additionally and/or optionally comprise one or morelight regulators 112. The light regulators 112 may be operatively linkedwith the light sensors 110 to receive measurements there from. In somepossible embodiments, the modulated light source 100 may comprise dataprocessing logic to determine trends in the raw measurement data. Themodulated light source 100 may perform database operations such asstoring and retrieving the measurement data before or after processing.The light regulators 112 may be configured to adjust, based on themeasurements, the relative and/or absolute strengths of color componentsin second light 108. It should be noted that, in some possibleembodiments, some or all of the foregoing may not be implemented in amodulated light source, but rather may be implemented as a part of alarger system that includes the modulated light source 100.

In some possible embodiments, a modulated light source as describedherein further comprises an age compensation unit. The age compensationunit may implement one or more age tracking algorithms to determine anaging state of (i) a modulation layer or (ii) a portion therein. In somepossible embodiments, the modulated light source may use the lightsensors 110 to determine whether the photon output (or the intensity ofregenerated light) from the modulation layer or light conversion unitunder incident light of a calibrated intensity has decreased from afirst time (e.g., when the modulated light source begins its operatinglife) to a second time (e.g., one year after the first time). When thedecrease in photon output is worse than a particular threshold, e.g.,the photon output at the second time is 80%, 90%, 95%, etc., of thephoton output at the first time, the modulated light source may activatea compensation mechanism to increase the photon output of the modulationlayer or the portion therein. For example, the modulated light source100 may increase the drive electric current or power to the first lightsources to boost the photon output. The increase of the drive electriccurrent or power to the first light sources may be calibrated based onthe detected decrease of the photon output as measured by the lightsensors.

4. Optical Stack

FIG. 1C illustrates an example configuration in which regenerated lightfrom an example modulation light source 100 may be used to illuminate anexample optical stack 114 in accordance with some possible embodimentsof the present invention. In some possible embodiments, the opticalstack 114 may be a part of a display system. As described herein, anoptical stack (e.g., 114) may comprise one or more of diffusers,polarization layers, light-focusing layers (e.g., made of one or morelight-redirecting optical prisms), reflective layers, substrate layers,thin films, retardation films, rubbing surfaces, light crystal layers,color and/or colorless filters, color enhancers, etc. For example, theoptical stack 114 may comprise a diffuser such that second light 108,even though it may have a portion of light directed off axis relative toa z-axis (e.g., towards a viewer of the display system), may beredirected and evenly distributed by the diffuser into outgoing lightthat is substantially in the direction of the z-axis. In some possibleembodiments, the light source 100 may comprise one or more opticalcomponents that are configured to diffuse and redirect light. In somepossible embodiments, the optical stack 114 or the light source 100 maycomprise one or more optical components such as reflective layers,polarization layers, optical filters, etc., to prevent first light 106from illuminating pixels in the display system and to allow second light106 to illuminate the pixels. It should be noted that, in some possibleembodiments, some or all of the foregoing components in an optical stackmay be implemented as a part of a modulated light source (e.g., 100), orinstead as a part of a larger system that include the modulated lightsource 100.

5. Patterned Modulation

FIG. 2A illustrates an example display system in which an examplemodulated light source (e.g., 100) with a light converter in the form ofa fully patterned modulation layer 202 is used to illuminate pixels ofthe display system, in accordance with some possible embodiments of thepresent invention. As illustrated, the modulated light source 100 maycomprise first light sources 104 in the form of a LED array 206. Invarious possible embodiments of the present invention, LEDs in array 206may comprise only a single type of LEDs, only two types of LEDs, onlythree types of LEDs, or more types of LEDs. In some possibleembodiments, all LEDs in array 206 may be required to emit light withwavelengths at least no more than the maximum of one or more thresholdwavelengths as determined by light conversion materials in modulationlayer 202. LEDs in array 206 may emit visible or invisible light. Forthe purpose of the present invention, other types of first light sourcesother than LEDs, including other modulated light sources whether quantumdot based or not, may be used in place of, or in addition to, the LEDarray 206. For example, in some possible embodiments, part ofregenerated light from modulation layer 202 may feedback to be part offirst light 106. In particular, in some possible embodiments, part ofregenerated blue light may be projected into a light guide to illuminatemodulation layer 202 to cause an increase of regenerated green or redlight, but a decrease of blue light, from modulation layer 202.

In some possible embodiments, the modulation layer 202 may comprisequantum dots of wide sensitivity. As used herein, the term “quantum dotsof wide sensitivity” means that the light intensity of the regeneratedlight from the quantum dots is responsive to the light intensity of theincident first light 106 that is from all types of LEDs in array 206. Insome possible embodiments, quantum dots of wide sensitivity mayefficiently convert most of the energy from incident first light to theenergy of regenerated light without much loss (e.g., to heat orineffective light regeneration). In an example, LED array 206 maycomprise a single type of blue LEDs. In this example, quantum dots areof wide sensitivity—if the regenerated light from these quantum dots isresponsive to the light intensity of the blue LEDs. In another example,LED array 206 may comprise two types of LEDs. In this example, quantumdots are of wide sensitivity—if the regenerated light from these quantumdots is responsive to the light intensities of both types of LEDs.

In some possible embodiments, the modulation layer 202 may comprisequantum dots of narrow sensitivity. As used herein, the term “quantumdots of narrow sensitivity” means that the light intensity of theregenerated light from the quantum dots is responsive to the lightintensity of the incident first light 106 that is from a particular onesof several types of LEDs in array 206. In an example, array 206 maycomprise two types (e.g., blue and red) of LEDs. In this example,quantum dots are of narrow sensitivity, if the regenerated light fromthese quantum dots is responsive to the light intensity of a particularone (e.g., blue but not red) of the two types of LEDs.

In some possible embodiments, the modulation layer 202 may comprisequantum dots of intermediate sensitivity. As used herein, the term“quantum dots of intermediate sensitivity” means that the lightintensity of the regenerated light from the quantum dots is responsiveto the light intensity of the incident first light 106 from two or more,but not all, of three or more types of LEDs in array 206. In an example,array 206 may comprise three types (e.g., ultraviolet, blue and red) ofLEDs. Quantum dots are of intermediate sensitivity, if the regeneratedlight from these quantum dots is responsive to the light intensities oftwo (e.g., blue and ultraviolet) but not all three of the three types ofLEDs.

In some possible embodiments, the modulation layer 202 may comprisequantum dots of narrow sensitivity. For example, in these embodiments,one type of quantum dots may be responsive to blue LEDs in array 206 butmay be unresponsive to other LEDs in array 206, while another type ofquantum dots may be responsive to ultraviolet LEDs in the light source100. In some possible embodiments, the modulation layer 202 may comprisequantum dots of wide sensitivity. For example, in these embodiments, alltypes of quantum dots may be responsive to all LEDs in array 206. Insome possible embodiments, the modulation layer 202 may comprise quantumdots of intermediate sensitivity only. For example, quantum dots may beresponsive to ultraviolet and blue, but not red LEDs, in array 206. Insome possible embodiments, the modulation layer 202 may comprise quantumdots of a mixture of one or more of narrow, intermediate, or widesensitivity. For example, a first type of quantum dots may be responsiveto ultraviolet incident light emitted from array 206; a second type ofquantum dots may be responsive to ultraviolet and blue incident lightemitted from array 206; and a third type of quantum dots may beresponsive to all ultraviolet, blue and red incident light emitted fromarray 206.

As used herein, the phrase “quantum dots are responsive to a type ofLEDs” refers to the quantum dots regenerating light in much greaterintensity when the incident light is provided by that type of LEDs inarray 206 than when the incident light is provided by another type ofLEDs in array 206 to which the quantum dots are not responsive. Forexample, quantum dots of blue color component may regenerate blue lightin much greater intensity when incident light is provided by a firsttype of LEDs than a second type of LEDs. For example, the first type ofLEDs may be blue LEDs in array 206 that emit light within a particularrange of wavelengths, while the second type of LEDs may be a differentcolor light LEDs in array 206 that emit light with a different range ofwavelengths. The difference in intensities of the regenerated light whenincident light is respectively provided by these two different types ofLEDs may be greater than a ratio of 10:1, 20:1, 50:1, 100:1, or adifferent ratio than the foregoing, in various possible embodiments ofthe present invention. In various possible embodiments, a differentratio may be configured to determine whether the quantum dots may bedeemed responsive to the first type of LEDs in array 206.

In some possible embodiments, a modulation layer (e.g., 202) asdescribed herein may comprise a plurality of light conversion unitsarranged in a particular pattern. For example, the modulation layer 202may, but is not limited to, comprise a grid pattern which may includeone or more light conversion units such as a first light conversion unit202-1, a second light conversion unit 202-2, and a third lightconversion unit 202-3, as illustrated in FIG. 2A. In some possibleembodiments, a light conversion unit in a patterned modulation layer maycomprise separate areas on the layer, each emitting a different colorcomponent. For example, a light conversion unit may comprise two or moredifferent types of quantum dots (e.g., type “QD 1”, type “QD 2”, andtype “QD 3”), each type occupying one or more different area andemitting a different color component.

As described herein, finer and coarser patterns may also be used todivide a modulation layer 202 into light conversion units. For example,in some possible embodiments in which light conversion units may beorganized different than illustrated in FIG. 2A, quantum dots in bothlight conversion units 202-1 and 202-2 in the illustrated embodimentsmay instead be grouped into a single light conversion unit. Likewise, insome other possible embodiments, quantum dots of each type in the lightconversion unit 202-2 in the illustrated embodiments may instead formthree individual light conversion units in their own right.

It should be noted that, for the purpose of the present invention, moreor fewer types of quantum dots may be used. For example, a lightconversion unit 202-1 may comprise one, two, three, four, five, or sixdifferent types of quantum dots that emit their respective colorcomponents. Additionally and/or alternatively, in some possibleembodiments, more than six types of quantum dots may be used. As aresult, a modulated light source as described herein may be used tosupport relatively wide color gamuts for certain high-end displaysystems.

In some possible embodiments, one or more LEDs or one or more LED binsmay be assigned to illuminate a light conversion unit. For example, aLED 206-1 may be assigned to illuminate one (e.g., 202-2) of the threelight conversion units illustrated in FIG. 2A, while a LED 206-2 may beassigned to illuminate another (e.g., 202-3) of the three lightconversion units.

In some possible embodiments, the light intensity for each LED in array206 may be controlled individually or together with light intensitiesfor one or more other LEDs in the array. For example, LED 206-1 may beset as in one of one or more “on” states (e.g., fully on, partially onat one of 2, 4, 8, 16, 32, 64, 128, 256 or more levels, etc.), while LED206-2 may be set in an “off” state.

In some possible embodiments, the LEDs in array 206 may be organizedinto LED bins; the light intensity for LEDs in each of the LED bins maybe controlled individually or together with light intensities for one ormore other LED bins in the array. LED bins may be organized by a sharedproperty of LEDs in the respective LED bins. In an example, LEDsemitting a particular color may be organized in a LED bin. In anotherexample, LEDs illuminating a particular geographic portion of a surfaceformed by the modulation layer 202 may be organized in a LED bin. Inanother example, LEDs emitting a particular color and in a particulargeographic portion of a surface formed by array 206 may be organized ina LED bin. Thus, for the purpose of the present invention, attributes ofLEDs, such as their locations, colors, etc., may be used to organize theLEDs into a plurality of LED bins whose intensity states may beindividually or collectively controlled.

In some possible embodiments, different LED bins occupy non-overlappingareas of a surface formed by array 206. For example, all three types ofquantum dots in a light conversion unit 202-2 may be illuminated by thesame LED or LED bin (e.g., 206-1).

In some possible embodiments, two or more of the LED bins may overlap ina common area of the surface as formed by array 206. For example, threeLED bins may be used to illuminate quantum dots in a light conversionunit 202-2. Furthermore, alternatively and/or additionally, each of thethree LED bins may emit first light 106 to which some, or all, of thequantum dots may respond.

6. Unpatterned Modulation

FIG. 2B illustrates an example display system in which an examplemodulated light source (e.g., 100) with a light converter in the form ofan unpatterned modulation layer 222 is used to illuminate pixels of thedisplay system, in accordance with some possible embodiments of thepresent invention. As illustrated, the modulated light source 100 maycomprise first light sources 104 in the form of LED array 206.

In some possible embodiments, the modulation layer 222 may comprise amixture of quantum dots of different color components. As used herein,the term “a mixture of quantum dots” means that two, or more types ofquantum dots as described herein may be mixed according to a set ratio,for example, calibrated to provide a particular white point for aspecific color gamut. In some possible embodiments, quantum dots ofdifferent color components (e.g., red, green, and blue; or QD 1, QD 2,and QD 3) may be evenly mixed. In some possible embodiments, the lightintensity of the regenerated light from the quantum dots is responsiveto (e.g., positively dependent on) the light intensity of the incidentfirst light 106 that is from all types of LEDs in array 206. In somepossible embodiments, proportional amounts of photons in different colorcomponents may be emitted from a mixture of quantum dots of differentcolor components. In some possible embodiments, disproportional amountsof photons in different color components may be emitted from a mixtureof quantum dots of different color components. In a possible embodiment,LED array 206 may comprise a single type of blue LEDs. In anotherpossible embodiment, LED array 206 may comprise two or more types ofLEDs such as three types (e.g., RGB) of LEDs. Selection of blue LEDs orRGB LEDs may be based on several factors including costs and color shiftproperties of the LEDs when driving electric currents and/or theoperating temperature vary. Quantum dots in the unpatterned modulationlayer 222 may be of narrow, intermediate, wide sensitivity, or a mixtureof two or more of the foregoing, if two or more types of LEDs are usedin array 206.

In some possible embodiments, an unpatterned modulation layer (e.g.,222) as described herein may comprise a plurality of light conversionunits. For example, the unpatterned modulation layer 222 may, but is notlimited to, comprise a grid pattern formed by a plurality of lightconversion units such as a light conversion unit 1 222-1 and a lightconversion unit 2 222-2, as illustrated in FIG. 2A. In some possibleembodiments, a light conversion unit in the unpatterned modulation layer222 may emit two or more different color components from a same area ona surface formed by the unpatterned modulation layer 222. For example, alight conversion unit may comprise a mixture of two or more differenttypes of quantum dots (e.g., type “QD 1”, type “QD 2”, and type “QD 3”),each type occupying a same area and emitting a different colorcomponent.

7. Light Modulation Tiles

A display system as described herein may use a modulation layer that isreplaceable after the display system is placed in use, for example, byan end customer, in some possible embodiments. For example, if themaximum intensity, and/or light regeneration efficiency, of regeneratedlight from a modulation layer 202 or 222 is detected to be out of aparticular range, or below a particular threshold after an end customerhas installed the display system at home, the entire modulation layer202 or 222 may still be replaced without replacing other components inthe display system.

In some possible embodiments, a display system as described herein maycomprise light modulation tiles. In some possible embodiments, each ofthe light modulation tiles may be individually replaced. In somepossible embodiments, a drive electric current to each of the lightmodulation tiles may be individually set. In some possible embodiments,each of the light modulation tiles may be individually set to one of“fully on”, “dimmed”, and “off” states.

FIG. 3 illustrates an example display system in which an examplemodulated light source (e.g., 100) comprises a modulation layer, whichmay be one of 202 and 222 illustrated in FIG. 2A and FIG. 2B, in theform of a light modulation tile array 300, in accordance with possibleembodiments of the invention. In some possible embodiments, the lightmodulation tile array 300 comprises a plurality of discrete lightmodulation tiles, each of which may be a light modulation tile (e.g.,302). In some possible embodiments, the maximum intensity, and/or lightregeneration efficiency, of regenerated light from each light modulationtile in the array 300 may be individually measured. Based on the resultsof the measurements, a light modulation tile such as 302 of FIG. 3 inthe array 300 may be replaced. Additionally and/or alternatively, insome possible embodiments, drive electric current may be adjusted up ordown to drive the light modulation tile 302 to regenerate light at aconfigured level of intensity. In some possible embodiments, one or morelight modulation tiles (e.g., 302) may be individually replaced in adisplay system as described herein without replacing other lightmodulation tiles in the display system.

FIG. 4A illustrates an example light modulation tile, in accordance withpossible embodiments of the invention. It should be noted that, while afigure herein may illustrate a single light modulation tile, amodulation layer as described herein may comprise a single lightmodulation tile in some possible embodiments, or a plurality of lightmodulation tiles in some other possible embodiments.

In some possible embodiments, a light modulation tile (e.g., 302) maycomprise a light guide 402 with substructures 404 that scatter incidentlight from a light source (406) into a multitude of directions, inaccordance with possible embodiments of the invention. In some possibleembodiments, the light source 406 is the whole, or a part, of the firstlight 104 as previously described. In some possible embodiments, thelight source 406 for the light modulation tile 302 may comprise one ormore LEDs or one or more LED bins, as previously described.

In some possible embodiments, the light source 406 may be placed belowthe light guide 402, relative to the vertical directions of FIG. 4Athrough FIG. 4B. In some possible embodiments, as illustrated, the lightsource 406 may be placed to the side of the light guide, relative to thehorizontal directions of FIG. 4A through FIG. 4B.

In some possible embodiments, substructures 404 may be cavities in thelight guide 402. In some possible embodiments, substructures 404 may beparticles that have one or more different refractive indices from arefractive index of much of the substance used to make the light guide402. In some possible embodiments, substructures 404 may be bumpystructures created in the light guide 402 during manufacturing.

In some possible embodiments, light from the light source 406 may beguided into the light guide 402 from a side direction as illustrated. Insome other possible embodiments, light from the light source 406 may beguided into the light guide 402 from one or more other directions thatare different from what is illustrated in FIG. 4A through FIG. 4B. Insome possible embodiments, the incident angles from the light source 406may be such that at least in parts of the light paths, for example,initial parts of the light paths, total reflection of the incident lightmay be accomplished inside the light guide 402, until the incident lighthits upon one of the substructures 404 or hits a quantum dot. In someembodiments, the light guide 402 may be configured to alter directionsof incident light from the light source 406 to incident into one or moreareas or surfaces where quantum dots are located.

FIG. 4B illustrates an example light modulation tile with a quantum dotsheet 408 disposed on the lower surface of a light guide (e.g., 402),relative to the vertical direction (e.g., a frontal viewing angletowards a viewer of a display panel) of FIG. 4B, in accordance withpossible embodiments of the present invention. FIG. 4C illustrates anexample light modulation tile with a quantum dot sheet 408 disposed onthe upper surface of a light guide (e.g., 402), relative to the verticaldirection (e.g., a frontal viewing angle towards a viewer of a displaypanel) of FIG. 4C, in accordance with possible embodiments of thepresent invention. In some possible embodiments, the quantum dot sheet408 may be formed by depositing (including but not limited to adhering,printing, sputtering, etc.) quantum dots onto the surface of the lightguide 402. In some possible embodiments, the quantum dot sheet may befirst formed and then laminated onto the lower or upper surface of thelight guide 402 as illustrated in FIG. 4B and FIG. 4C. FIG. 4Dillustrates an example light modulation tile with quantum dots 410 maybe dispersed within a light guide (e.g., 402), in accordance withpossible embodiments of the present invention.

In some possible embodiments, the substructures 404 may be evenlydistributed in the light guide 402. In some other possible embodiments,the substructures 404 may be distributed unevenly in the light guide402. In an example, the substructures 404 may be concentrated near wherethe quantum dot sheet 408 is located. In another example, alternativelyand/or additionally, the substructures 404 may be concentrated away fromwhere the quantum dot sheet 408 is located.

In some possible embodiments, the modulated light source, or any lightmodulation tile therein, may comprise additional optical components. Forexample, a light modulation tile (e.g., 302) may additionally and/oroptionally comprise polarization films, retardation films, lightrecycling films, prisms, mirrors, bumpy surfaces, impurities, dopants,materials of differing refractive indices, light valves, etc., for thepurpose of retaining the first light from the light source 406 withinthe light guide 402, or from escaping out of the light guide 402 towardsrestricted directions, in the light modulation tile 302 until hittingthe quantum dots and being converted to regenerated light by the quantumdots, while causing regenerated light to be emitted out of the lightmodulation tile 302 to illuminate a display panel.

8. Intensity States

Finer and coarser patterns may also be used to divide a modulation layerinto light conversion units. It should be noted that for the purpose ofthe present invention, more or fewer types of quantum dots may be used.For example, a light conversion unit 202-1 may comprise one, two, three,four, five, or six different types of quantum dots that emit theirrespective color components. Additionally and/or alternatively, in somepossible embodiments, more than six types of quantum dots may be used.As a result, a modulated light source with an unpatterned modulationlayer as described herein may be used to support a relatively wide colorgamut.

In some possible embodiments, one or more LEDs or one or more LED binsmay be assigned to illuminate a light conversion unit, which may be awhole, or a part, of a light modulation tile (e.g., 302). For example,LED 206-4, LED 206-5, and LED 206-6 may be assigned to illuminate lightconversion unit 1 222-1, light conversion unit 2 222-2, and anotherlight conversion unit (not shown), respectively.

In some possible embodiments, intensity states of LEDs or LED bins thatilluminate a set of pixels may be dynamically set. In some possibleembodiments, the intensity states may be set based on average luminancelevels required for the pixels in one or more images that are to bedisplayed. The average luminance levels may be computed based on imagedata for the images. In these images, some areas (e.g., on an imageportraying the interior of a church including brightly illuminatedwindows) of the display panel may appear bright, while other areas(e.g., interior sections of the church with fine architectural details)of the display panel may appear dimmed Settings of different “on” statesof LEDs to states (e.g., dimmed) other than fully “on” and “off” basedon the image data produces a display system that has a relatively highdynamic range for contrast levels and thus is able to display relativelydetailed images. For example, the intensity states of LEDs 206-1 through206-6 as illustrated in FIG. 2A and FIG. 2B may be fully on, partiallyon, and off, respectively.

While the display system is configured to support a large variation ofbrightness levels (e.g., local dimming in an area of pixels illuminatedby light conversion unit 2 222-2) for different areas of images, thedisplay system is also configured to support a fine control ofbrightness levels within each of the areas, in order to showhigh-quality images that comprise many fine details. In some possibleembodiments, the brightness levels within each of these areas, asperceived by a viewer, may be further controlled on the basis ofindividual pixels or pixel blocks based on the image data using lightvalves and color filters in these pixels. For example, a pixel maycomprise subpixels of different colors whose brightness levels may beindividually controlled on a subpixel basis to produce a precise pointin a color gamut, as appropriate for the image data.

As discussed earlier, the light intensity of the color componentgenerated by the quantum dots may be selectively responsive to the lightintensities of one, two, or a limited number, but not all, of types ofLEDs. The selective responses of quantum dots to different LEDs allow aparticular color component to be enhanced while another color componentis attenuated as required by the image data. Thus, a display system mayproduce colors that are relatively free of halos and/or light pollutionfrom nearby colors or nearby pixels or sub-pixels. For example, if aparticular region of pixels should display a red color, one or moreselective LED bins that cause red color component in the regeneratedlight may be turned on, while other LED bins that cause other colorcomponents in the regenerated light may be turned off or set to dimmedstates. Thus, a display system with a modulated light source asdescribed herein may have a relatively wide color gamut (capable ofexpressing deeply saturated colors), and thus is able to displayrelatively accurate colored images.

In some possible embodiments, a display system as described hereinfurther comprises a display panel 208 comprising a plurality of pixelswhich may, but are not limited to, include pixels 208-1 and 208-2, asillustrated in FIG. 2A and FIG. 2B. As illustrated, each pixel may beilluminated with second light with color components in the prescribedrange of wavelengths, as regenerated by one or more light conversionunits in the modulation layer (e.g., 202 and 222).

In some possible embodiments, a display system as described herein maycomprise an optical stack (e.g., 204 of FIGS. 2A and 206 of FIG. 2B).The optical stack or some or all components therein may be placed beforeor after the modulation layer.

In some possible embodiments, a display system with modulated lightsources as described herein is configured to implement one or more of aplurality of wide color gamuts, which may be standard-based. In somepossible embodiments, the display system may be configured with threetypes of quantum dots in the modulation layer (e.g., 202 and 222) toimplement a particular wide color gamut such as Academy Color EncodingSpace (ACES) P3, or Digital Cinema Initiative color space, or a widercolor gamut. In some possible embodiments, the display system may beconfigured with more than three types of quantum dots (e.g., 4, 5, 6, ormore types of quantum dots) in the modulation layer (e.g., 202 and 222)to implement a specific color gamut that is even wider than theforegoing color gamuts. For example, the display system may implement aparticular wide color gamut such as ACES P4, P5, P6 or larger.

Color gamuts as described herein may substantially conform to a RGBcolor space that is associated with the International TelecommunicationUnion Radio Communication Sector (ITU-R) BT.709 Recommendation standardof the International Telecommunications Union (ITU). The color spacesmay substantially conform to at least one of the RGB color spaces thatare associated with the ACES standard of the Academy of Motion PictureArts and Sciences (AMPAS), the color space standard of the DigitalCinema Initiative (DCI), or the Reference Input Medium Metric/ReferenceOutput Medium Metric (RIMM/ROMM) standard.

FIG. 7 depicts an example color gamut, according to an embodiment of thepresent invention. The color gamut may comprise a spectrum locus 702.Within spectrum locus 702 are gamut 704, which relates to one of theACES color spaces, gamut 706, which relates to the DCI color space, andgamut 708, which relates to the BT-709 color space. It should be notedthat in various possible embodiments of the present invention, othercolor spaces not depicted, which may include a color space relating toReference Input/Output Medium Metric RGB Color Encodings (RIMM/ROMMRGB), may also be configured for a display system that implements lightmodulation techniques as described herein.

9. Modulated Light Source Controller

As shown in FIG. 5, a display system as described herein may comprise amodulated light source 100 and a modulated light source controller 502configured to receive image data from an image data source 506. Each LEDand/or each LED bin in the modulated light source 100 may be set with alocal intensity state. The modulated light source controller 502 may beconfigured to set the operational states of the LEDs or LED bins toprovide the desired dimming level for an area of a display panel in thedisplay system based on the image data received from the image datasource 506. The image data may be provided by the image data source 506in a variety of ways including from over-the-air broadcast, a set-topbox, a networked server coupled to the display system, and/or a storagemedium. The modulated light source controller 502 may comprise samplinglogic 504 to sample image data and compute, based on the image data,luminance values of a pixel, a group of pixels, or a portion of anilluminated surface such as a surface of the diffuser or the displaypanel. The results of sampling and computing may be used by themodulated light source controller 502 to drive the LEDs or LED bins.

In some possible embodiments, LEDs or LED bins may have a singleoperational state: fully on. In some possible embodiments, LEDs or LEDbins may have two or more operational states: off, on (fully on or amaximum intensity level), and one or more intermediate intensity levels(dimmed states).

In some possible embodiments, based on the image data, a modulated lightsource controller as described herein may determine that a centraldesignated portion on the display panel illuminated by regenerated lightexcited by first light from an LED or an LED bin should be illuminatedat a certain level and accordingly determine that the LED or LED binshould be set in a corresponding operational state. This determinationmay be repeated by the modulated light source logic for all the LEDs orLED bins in the system.

The modulated light source controller 502 may implement one of severalpossible algorithms to determine an appropriate intensity level for anLED or LED bin. In one possible embodiment, the intensity level may beset to be proportional to the desired illumination level for thedesignated portion on the display panel. In another possible embodiment,the intensity level determination may take into consideration otherfactors such as the desired illumination level of a particular color,ageing of light conversion units involved, etc.

10. Example Process Flow

FIG. 6 illustrates an example process flow according to a possibleembodiment of the present invention. In some possible embodiments, oneor more computing devices or components in a display system may performthis process flow.

In block 610, a modulated light source (e.g., 100) causes one or morefirst light sources 104 to emit first light (e.g., 106). The first light106 may comprise one or more first color components that occupy beyondone or more prescribed ranges of light wavelengths.

In block 620, the modulated light source 100 causes the first light 106to illuminate a light converter (e.g., a light modulation layer 102) soas to convert the first light into second light (or regenerated light106). The second light comprises one or more second color componentsthat occupy a range within the one or more prescribed ranges of lightwavelengths. Strengths (or intensity levels) of the one or more secondcolor components in the second light may be monitored and regulated toproduce a particular point within a specific color gamut. As describedherein, this particular point may be maintained by the modulated lightsource over an extended period of 100, 500, 1000, or more or fewer hoursin various possible embodiments. As described herein, this particularpoint may also be maintained by the modulated light source over anextended range of operating temperatures (−40-100° C., −20-80° C., etc.)in various possible embodiments.

In some possible embodiments, the modulated light source may compriseone or more light sensors configured to measure the strengths of thefirst and/or second color components. In some possible embodiments, themodulated light source may further comprise one or more light regulatorsconfigured to adjust, based on the measurements, the strengths of thefirst and/or second color components.

In some possible embodiments, the first light sources are LEDs or LEDbins. In some possible embodiment, the LEDs in the modulated lightsource comprise all single colored LEDs, for example, blue LEDs. In somepossible embodiments, the LEDs in the modulated light source comprisemulti-colored LEDs such as RGB LED, white LEDs, or different types ofLEDs.

In some possible embodiments, the light converter comprises one or moregroups of quantum dots, each group of quantum dots being configured toproduce a color component within one of the prescribed ranges of lightwavelengths. In some possible embodiments, the quantum dots may bedeposited on a substrate within the modulated light source. In somepossible embodiments, the quantum dots may be laminated onto a surfacewithin the modulated light source. In some possible embodiments, each ofthe quantum dots is enclosed in one or more protective materials withinthe modulated light sources.

In some possible embodiments, the modulated light source is configuredto confine the first light within the modulated light source and to emitthe second light (or regenerated light).

In some possible embodiments, the light emitted out of the modulatedlight source may be configured to shine through a diffuser. In somepossible embodiments, the light emitted out of the modulated lightsource may be configured to shine onto a display panel.

In some possible embodiments, the light converter (or light modulationlayer) in the modulated light source may comprise an array of lightconversion units. Each light conversion unit may be configured toproduce a part of a single color component in the second colorcomponents in the second light. In some possible embodiments, each lightconversion unit may be configured to produce a part of all colorcomponents in the second color components in the second light. In somepossible embodiments, each light conversion unit is configured toproduce a part of some but not all color components in the second colorcomponents in the second light. In some possible embodiments,intensities of one or more parts of one or more color components,regenerated by each light conversion unit, in the second light ismonitored and regulated to produce the particular point within thespecific color gamut.

In some possible embodiments, the modulated light source may beconfigured to operate within a range of temperatures; strengths of theone or more second color components in the second light are monitoredand regulated to produce the same particular point within the samespecific color gamut for any temperature in the range of temperatures.

In some possible embodiments, a light source system may comprise amodulated light source as described in the foregoing and a modulatedlight source logic comprising a plurality of data inputs and datacontrols coupled to the light source. The modulated light source logicmay be configured to monitor and regulate strengths of one or more colorcomponents in light emitted out of the light source to produce aparticular point within a specific color gamut.

11. Equivalents, Extensions, Alternatives and Miscellaneous

In the foregoing particularation, possible embodiments of the inventionhave been described with reference to numerous particular details thatmay vary from implementation to implementation. Thus, the sole andexclusive indicator of what is the invention, and is intended by theapplicants to be the invention, is the set of claims that issue fromthis application, in the particular form in which such claims issue,including any subsequent correction. Any definitions expressly set forthherein for terms contained in such claims shall govern the meaning ofsuch terms as used in the claims. Hence, no limitation, element,property, feature, advantage or attribute that is not expressly recitedin a claim should limit the scope of such claim in any way. Theparticularation and drawings are, accordingly, to be regarded in anillustrative rather than a restrictive sense.

In some possible embodiments, quantum dots that regenerate light atparticular colors may replace color filters. Thus, in these embodiments,light valves such as one or more LCD panels comprising pixels orsub-pixels may be further away from a viewer than, and behind, thequantum dots. For example, a sub-pixel that is to transmit green lightmay be coated with quantum dots that emit regenerated green light; asub-pixel that is to transmit blue light may be coated with quantum dotsthat emit regenerated blue light; a sub-pixel that is to transmit redlight may be coated with quantum dots that emit regenerated red light.Other color systems other than RGB may also be used. For instance, 3, 4,or five different color lights may be used in a display system asdescribed herein. In some embodiments, instead of using color filters toproduce colors, quantum dots that regenerate these different colors maybe coated on pixels or light valves, whether these pixels or lightvalves are LCD-based or not.

In some possible embodiments, a modulated light source (e.g., that usesquantum dots to regenerate lights at very precise wavelengths inprescribed ranges) as described herein may be used in various types ofconfigurations including those with zero, one, two, or more displaypanels. A display panel as described herein may or may not be LCD-based.In some embodiments, a modulated light source herein may be used in asystem with two display panels. In an example, one display panel in sucha system may be a black-and-white display panel while another displaypanel in the same system may be a color display panel. Additionallyand/or optionally, one display panel in a system may be a hightransmission display panel while another display panel in the samesystem may be a lower transmission display panel. Furthermore, amodulated light source herein may support two or more display panels inany order. For example, a black-and-white display panel may be before orafter a color display panel. Additionally and/or optionally, a hightransmission display panel may be before or after a low transmissiondisplay panel. A modulated light herein may be used in a system thatuses various types of display panels. In an example, a display panel maybe based on electrowetting, plasma, front projection, liquid crystal,etc. Liquid crystal display panels may comprise light valves that usevarious types of liquid crystal materials, organic (e.g., cholesterol),inorganic, lyotropic liquid crystals, electrically controlledbirefringence (ECB) liquid crystals, etc.

In some possible embodiments, a modulated light source (e.g., that usesquantum dots to regenerate lights at very precise wavelengths inprescribed ranges) as described herein may be used in various types ofoptical configurations including zero, one, two, or more opticalcomponents of a kind. For example, in some embodiments, a modulatedlight source herein may be used in a system with zero, one, two, or morepolarizers.

In some possible embodiments, a modulated light source herein maycomprise different types of LEDs and different types of quantum dots.For example, in some possible embodiments, two types of LEDs may beused. Blue LEDs or first frequency LEDs may be used to regenerate bluequantum dot frequency light and red quantum dot frequency light.Optionally and/or alternatively, a part of the blue LED light may bedirectly passed through to illuminate a target such as a diffuser or adisplay panel, while the remaining part of the blue LED light may beused to regenerate the red quantum dot frequency light. Additionallyand/or optionally, green LEDs or second frequency LEDs may be used toregenerate green quantum dot frequency light. Optionally and/oralternatively, the green LED light may be directly passed through toilluminate a target such as a diffuser or a display panel. In somepossible embodiments, techniques as described herein may modulate and/orcontrol blue and red light as a first set of light, and modulate and/orcontrol green light separately as a second set of light, therebyeliminating possible overlap between these two sets of light that wouldexists should light of blue, green, and red be modulated and controlledtogether.

In some possible embodiments, a light converter or regenerator asdescribed herein may be configured to control its input sensitivity toproduce a P5 or P6 color gamut. Alternatively and/or optionally, quantumdots may be added on top of one or more LEDS (e.g., each blue LED) suchthat each LED set can have different compositions of color componentsaccording to the local region of color as determined from image data ofone or more images to be rendered. Thus, techniques as described hereinallow controlling the white point and primary color components in localregions with a light converter and regenerator as described herein thatcomprises quantum dots.

It should be noted that a modulated light source as described herein maybe configured to generate different color components for a differentimage or image frame. For example, in some possible embodiments in whichimages are presented in a sequential manner, the modulated light sourcemay generate different color components for different images of asequence. In some possible embodiments, a single image frame may besequentially illuminated by a modulated light source as described hereinin two or more time intervals during each of which different colorcomponents may be used to illuminate a display panel when pixels of thedisplay panel are loaded with image data of the same image frame. Forexample, in a first time interval, an image frame may be presented withred and blue color components while in a second time interval, the imageframe may be presented with a green color component. In a particularembodiment, the frame rate may be reduced proportionally. For example, ahalf frame rate may be used. Each of the frame at the half frame ratemay comprise two illumination intervals during each of which a differentset of color components from a light source as described herein is used.

What is claimed is:
 1. A light source, comprising: one or more firstlight sources that are configured to emit first light comprising one ormore first color components that occupy a first range that is beyond oneor more prescribed ranges of light wavelengths; and a light converterconfigured to be illuminated by the first light and to convert the firstlight into second light, the second light comprising one or more secondcolor components that occupy a second range within the one or moreprescribed ranges of light wavelengths, each of the one or more secondcolor components in the second light having strengths monitored andregulated to produce a particular point within a specific color gamut,wherein the light converter comprises one or more light modulationtiles, at least one of which is replaceable without replacing othercomponents including other light modulation tiles in a display system.2. The light source as recited in claim 1, further comprising: one ormore light sensors configured to measure the strengths of the one ormore second color components; and one or more light regulatorsconfigured to adjust, based on the measurements, the strengths of theone or more second color components.
 3. The light source as recited inclaim 1, wherein the first light sources comprise light-emitting diodes.4. The light source as recited in claim 3, wherein the light-emittingdiodes comprise single colored light-emitting diodes.
 5. The lightsource as recited in claim 3, wherein the light-emitting diodes comprisemulti-colored light-emitting diodes.
 6. The light source as recited inclaim 1, wherein the light converter comprises one or more groups ofquantum dots, each group of quantum dots being configured to produce acolor component within one of the prescribed ranges of lightwavelengths.
 7. The light source as recited in claim 1, wherein thelight source is configured to modulate or control a first set of lightcolors and to modulate or control one or more other sets of light colorsseparately from controlling the first set of light colors.
 8. The lightsource as recited in claim 1, wherein a quantum dot sheet is disposed ona surface of at least one light modulation tile in the one or more lightmodulation tiles.
 9. The light source as recited in claim 1, whereinquantum dots are dispersed within at least one light modulation tile inthe one or more light modulation tiles.
 10. The light source as recitedin claim 1, wherein the light source is configured to confine the firstlight within the light source and to emit the second light.
 11. Thelight source as recited in claim 1, wherein the light source isconfigured to shine the second light through a diffuser.
 12. The lightsource comprising: one or more first light sources that are configuredto emit first light comprising one or more first color components thatoccupy a first range that is beyond one or more prescribed ranges oflight wavelengths; and a light converter configured to be illuminated bythe first light and to convert the first light into second light, thesecond light comprising one or more second color components that occupya second range within the one or more prescribed ranges of lightwavelengths, each of the one or more second color components in thesecond light having strengths monitored and regulated to produce aparticular point within a specific color gamut, wherein the light sourceis configured to shine the second light through a display panel.
 13. Thelight source as recited in claim 1, wherein the light convertercomprises an array of light conversion units and wherein each lightconversion unit is configured to produce a part of a single colorcomponent in the second color components in the second light.
 14. Thelight source comprising: one or more first light sources that areconfigured to emit first light comprising one or more first colorcomponents that occupy a first range that is beyond one or moreprescribed ranges of light wavelengths; and a light converter configuredto be illuminated by the first light and to convert the first light intosecond light, the second light comprising one or more second colorcomponents that occupy a second range within the one or more prescribedranges of light wavelengths, each of the one or more second colorcomponents in the second light having strengths monitored and regulatedto produce a particular point within a specific color gamut, wherein thelight converter comprises an array of light conversion units and whereineach light conversion unit is configured to produce a part of all colorcomponents in the second color components in the second light.
 15. Thelight source as recited in claim 1, wherein the light convertercomprises an array of light conversion units and wherein each lightconversion unit is configured to produce a portion of the second colorcomponents in the second light.
 16. The light source as recited in claim1, wherein the light converter comprises an array of light conversionunits and wherein intensities of one or more parts of one or more colorcomponents, from each light conversion unit, in the second light ismonitored and regulated to produce the particular point within thespecific color gamut.
 17. The light source as recited in claim 1,wherein the light source is configured to operate within a range oftemperatures and wherein the one or more second color components in thesecond light having strengths monitored and regulated to produce theparticular point within the specific color gamut for any temperature inthe range of temperatures.
 18. The light source comprising: one or morefirst light sources that are configured to emit first light comprisingone or more first color components that occupy a first range that isbeyond one or more prescribed ranges of light wavelengths; and a lightconverter configured to be illuminated by the first light and to convertthe first light into second light, the second light comprising one ormore second color components that occupy a second range within the oneor more prescribed ranges of light wavelengths, each of the one or moresecond color components in the second light having strengths monitoredand regulated to produce a particular point within a specific colorgamut, wherein the specific color gamut comprises one of an AcademyColor Encoding Space (ACES) color space, a Digital Cinema Initiative(DCI) color space, an International Telecommunication Union (ITU) colorspace, or a Reference Input/Output Medium Metric RGB Color Encodings(RIMM/ROMM RGB) color space.
 19. The light source comprising: one ormore first light sources that are configured to emit first lightcomprising one or more first color components that occupy a first rangethat is beyond one or more prescribed ranges of light wavelengths; and alight converter configured to be illuminated by the first light and toconvert the first light into second light, the second light comprisingone or more second color components that occupy a second range withinthe one or more prescribed ranges of light wavelengths, each of the oneor more second color components in the second light having strengthsmonitored and regulated to produce a particular point within a specificcolor gamut, wherein the light source is configured to illuminate zero,one, two or more display panels in a display system.
 20. The lightsource comprising: one or more first light sources that are configuredto emit first light comprising one or more first color components thatoccupy a first range that is beyond one or more prescribed ranges oflight wavelengths; and a light converter configured to be illuminated bythe first light and to convert the first light into second light, thesecond light comprising one or more second color components that occupya second range within the one or more prescribed ranges of lightwavelengths, each of the one or more second color components in thesecond light having strengths monitored and regulated to produce aparticular point within a specific color gamut, wherein the lightconverter comprises quantum dots that cover one or more light valves andimpart one or more different colors for the one or more light valves.